Split groups and ban groups

core/migrations/0043_bangroup_alter_group_description_alter_user_groups_and_more.py

@@ -0,0 +1,164 @@
+# Generated by Django 4.2.17 on 2024-12-31 13:30
+
+import django.contrib.auth.models
+import django.db.models.deletion
+from django.conf import settings
+from django.db import migrations, models
+from django.db.migrations.state import StateApps
+
+
+def migrate_ban_groups(apps: StateApps, schema_editor):
+    Group = apps.get_model("core", "Group")
+    BanGroup = apps.get_model("core", "BanGroup")
+    ban_group_ids = [
+        settings.SITH_GROUP_BANNED_ALCOHOL_ID,
+        settings.SITH_GROUP_BANNED_COUNTER_ID,
+        settings.SITH_GROUP_BANNED_SUBSCRIPTION_ID,
+    ]
+    # this is a N+1 Queries, but the prod database has a grand total of 3 ban groups
+    for group in Group.objects.filter(id__in=ban_group_ids):
+        # auth_group, which both Group and BanGroup inherit,
+        # is unique by name.
+        # If we tried give the exact same name to the migrated BanGroup
+        # before deleting the corresponding Group,
+        # we would have an IntegrityError.
+        # So we append a space to the name, in order to create a name
+        # that will look the same, but that isn't really the same.
+        ban_group = BanGroup.objects.create(
+            name=f"{group.name} ",
+            description=group.description,
+        )
+        perms = list(group.permissions.values_list("id", flat=True))
+        if perms:
+            ban_group.permissions.add(*perms)
+        ban_group.users.add(
+            *group.users.values_list("id", flat=True), through_defaults={"reason": ""}
+        )
+        group.delete()
+        # now that the original group is no longer there,
+        # we can remove the appended space
+        ban_group.name = ban_group.name.strip()
+        ban_group.save()
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ("auth", "0012_alter_user_first_name_max_length"),
+        ("core", "0042_invert_is_manually_manageable_20250104_1742"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="BanGroup",
+            fields=[
+                (
+                    "group_ptr",
+                    models.OneToOneField(
+                        auto_created=True,
+                        on_delete=django.db.models.deletion.CASCADE,
+                        parent_link=True,
+                        primary_key=True,
+                        serialize=False,
+                        to="auth.group",
+                    ),
+                ),
+                ("description", models.TextField(verbose_name="description")),
+            ],
+            bases=("auth.group",),
+            managers=[
+                ("objects", django.contrib.auth.models.GroupManager()),
+            ],
+            options={
+                "verbose_name": "ban group",
+                "verbose_name_plural": "ban groups",
+            },
+        ),
+        migrations.AlterField(
+            model_name="group",
+            name="description",
+            field=models.TextField(verbose_name="description"),
+        ),
+        migrations.AlterField(
+            model_name="user",
+            name="groups",
+            field=models.ManyToManyField(
+                help_text="The groups this user belongs to. A user will get all permissions granted to each of their groups.",
+                related_name="users",
+                to="core.group",
+                verbose_name="groups",
+            ),
+        ),
+        migrations.CreateModel(
+            name="UserBan",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                (
+                    "created_at",
+                    models.DateTimeField(auto_now_add=True, verbose_name="created at"),
+                ),
+                (
+                    "expires_at",
+                    models.DateTimeField(
+                        blank=True,
+                        help_text="When the ban should be removed. Currently, there is no automatic removal, so this is purely indicative. Automatic ban removal may be implemented later on.",
+                        null=True,
+                        verbose_name="expires at",
+                    ),
+                ),
+                ("reason", models.TextField(verbose_name="reason")),
+                (
+                    "ban_group",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="user_bans",
+                        to="core.bangroup",
+                        verbose_name="ban type",
+                    ),
+                ),
+                (
+                    "user",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="bans",
+                        to=settings.AUTH_USER_MODEL,
+                        verbose_name="user",
+                    ),
+                ),
+            ],
+        ),
+        migrations.AddField(
+            model_name="user",
+            name="ban_groups",
+            field=models.ManyToManyField(
+                help_text="The bans this user has received.",
+                related_name="users",
+                through="core.UserBan",
+                to="core.bangroup",
+                verbose_name="ban groups",
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="userban",
+            constraint=models.UniqueConstraint(
+                fields=("ban_group", "user"), name="unique_ban_type_per_user"
+            ),
+        ),
+        migrations.AddConstraint(
+            model_name="userban",
+            constraint=models.CheckConstraint(
+                check=models.Q(("expires_at__gte", models.F("created_at"))),
+                name="user_ban_end_after_start",
+            ),
+        ),
+        migrations.RunPython(
+            migrate_ban_groups, reverse_code=migrations.RunPython.noop, elidable=True
+        ),
+    ]